Image forming apparatus having a changeable adjustment toner image positioning feature

Abstract

In an image forming apparatus in which an maximum image width for image forming is smaller than the sum of a maximum recording material width of a usable recording material and length of two pattern images for a density correction and a registration deviation correction in a recording material width direction, an area for forming the pattern image is changed between the case where the recording width of a practically usable recording material is not more than a threshold value and the case where the recording width exceeds the threshold value. When the recording width is not more than the threshold value, the pattern image is formed on a non-sheet passing section image area, and when the recording width exceeds the threshold value, the pattern image is formed on a sheet interval between the trailing edge of a proceeding recording material and the leading edge of a subsequent material.

1. An image forming apparatus comprising:
 an image bearing member; 
 an image forming unit for forming a toner image on the image bearing member; 
 a transfer unit for transferring the toner image formed on the image bearing member to a recording material; 
 a detection unit for detecting an adjustment toner image formed by the image forming unit; 
 an adjustment unit for adjusting an image forming condition of the image forming unit based on the detected result of the detection unit; 
 a determination unit for determining whether to execute the adjusting control by the adjustment unit; 
 a control unit configured to execute a first mode in which the image forming unit forms the adjusting toner image inbetween before and after the ordinary images in a moving direction of the image bearing member, when ordinary images are continuously formed on a plurality of recording materials, and a second mode in which the image forming unit forms the adjusting toner image and the ordinary images in parallel in a direction orthogonal to a conveyance direction of the image bearing member so that at least a part of the adjusting toner is superimposed on the ordinary image in the moving direction of the image bearing member, when ordinary images are continuously formed on a plurality of recording materials and; 
 a selection unit configured to select the first mode when a width in a direction orthogonal to a conveyance direction of the recording material to which the image formed on the image bearing member is transferred after it is determined to execute the adjusting control, is wider than the predetermined threshold, and select the second mode when a width in a direction orthogonal to a conveyance direction of the recording material is not wider than the predetermined threshold. 
 
   
   
     2. The image forming apparatus according to  claim 1 , wherein the width of an area within a maximum image forming area configured to form the image on the image bearing member by the image forming unit, and outside the conveyance area of the recording material having a maximum size is smaller than the adjustment toner image in a width direction orthogonal to a moving direction of the image bearing member. 
   
   
     3. The image forming apparatus according to  claim 1 , wherein the adjustment toner image is formed in a position where at least a part of the adjustment toner image is superimposed on an area corresponding to the conveyance area of the recording material having a maximum size, and also in a corresponding position outside the conveyance area of the recording material having a predetermined size smaller than the maximum size in a width direction orthogonal to a moving direction of the image bearing member. 
   
   
     4. The image forming apparatus according to  claim 1 , wherein the threshold value can be changed on the basis of a width size of the adjustment toner image. 
   
   
     5. The image forming apparatus according to  claim 1 , further comprising:
 a detection unit for detecting the adjustment toner image, wherein an image forming condition is controlled on the basis of the detected result of the detection unit. 
 
   
   
     6. The image forming apparatus according to  claim 5 , wherein the detection unit comprises a density detection unit for detecting the density of the adjustment toner image, and wherein the adjustment unit adjusts the density of the toner image formed by the image forming unit based on the detected result. 
   
   
     7. The image forming apparatus according to  claim 5 , wherein the detection unit comprises a position detection unit for detecting the position of the adjustment toner image, and wherein the adjustment unit adjusts a position in which the toner image is formed, based on the detected result. 
   
   
     8. The image forming apparatus according to  claim 1 , wherein a conveyance interval of the recording material on which a normal image is formed when the second mode is executed, is narrower than when the first mode is executed, in the case of forming the adjustment toner image during a job for continuously forming the image on the recording material. 
   
   
     9. An image forming apparatus comprising:
 an image bearing member; 
 an image forming unit for forming a toner image on the image bearing member, the image forming unit allowing formation of a waste toner image which is not transferred to a recording material and is forcibly disposed; 
 a transfer unit for transferring the toner image formed on the image bearing member to the recording material; 
 a removing unit for removing the waste toner image; 
 a judgment unit for judging whether formation of the waste toner image is necessary; 
 a control unit configured to execute a first mode for controlling image forming timing so as to form the waste toner image when the formation of the waste toner image was judged necessary in the judgment unit and to form a normal image after the formation of the waste toner image is completed during a period from reception of an image forming start signal to completion of image forming, and a second mode for controlling image forming timing so as to form the waste toner image in parallel with the normal image; and 
 a selection unit which can select a first mode when a size of the recording material in a width direction orthogonal to a direction of conveyance of the recording material to which an image is transferred after the formation of the waste toner image is judged necessary, is larger than a predetermined threshold value, and a second mode when the size is smaller than the predetermined threshold value. 
 
   
   
     10. The image forming apparatus according to  claim 9 , wherein the width of an area within a maximum image forming area configured to form the image on the image bearing member by the image forming unit, and outside the conveyance area of the recording material having a maximum size is smaller than the adjustment toner image in a width direction orthogonal to a rotational direction of the image bearing member. 
   
   
     11. The image forming apparatus according to  claim 10 , wherein the width of an area within a maximum image forming area configured to form an image on the image bearing member by the image forming unit, and outside the conveyance area of the recording material having a maximum size in a width direction orthogonal to a rotational direction of the image bearing member is smaller than the width of the waste toner image. 
   
   
     12. The image forming apparatus according to  claim 11 , wherein the waste toner image is formed in a position where at least a part of the waste toner image is superimposed on an area corresponding to the conveyance area of the recording material having a maximum size, and in a corresponding position outside the conveyance area of the recording material having a predetermined size smaller than the maximum size in a width direction orthogonal to a rotational direction of the image bearing member. 
   
   
     13. An image forming apparatus comprising:
 an image bearing member; 
 an image forming unit for forming a toner image on the image bearing member; 
 a transfer unit for transferring the toner image formed on the image bearing member to a recording material; 
 a detection unit for detecting an adjustment toner image formed by the image forming unit; 
 an adjustment unit for adjusting the image forming condition of the image forming unit based on the detected result of the detection unit; 
 wherein the image forming unit forms the adjusting toner image and the ordinary images in parallel in a direction orthogonal to a conveyance direction of the image bearing member so that at least a part of the adjusting toner is superimposed on the ordinary image in the moving direction of the image bearing member, when ordinary images are continuously formed on a plurality of recording materials that are equal to or less than the predetermined width; and 
 wherein the image forming unit forms the adjusting toner image inbetween before and after the ordinary images in a moving direction of the image bearing member, when ordinary images are continuously formed on a plurality of recording materials which are wider than the predetermined width. 
 a control unit configured to execute a first mode for forming the adjustment toner image between the image forming areas of the first recording material and the second recording material by widening the conveyance interval between the first recording material and the subsequent second recording material when the adjustment toner image is formed after the image forming corresponding to the first recording material is made, and a second mode for controlling so as to form the adjustment toner image in parallel with the image forming of the second recording material during a job for continuously forming the image on a plurality of the recording materials; and 
 a selection unit which can select a first mode when a width size of the second recording material orthogonal to a direction of conveyance of the second recording material is larger than a predetermined threshold value, and a second mode when a width size of the second recording material orthogonal to a direction of conveyance of the second recording material is smaller than the predetermined threshold value. 
 
   
   
     14. The image forming apparatus according to  claim 13 , wherein the width of an area within a maximum image forming area configured to form the image on the image bearing member by the image forming unit, and outside the conveyance area of the recording material having a maximum size is smaller than the adjustment toner image in a width direction orthogonal to a rotational direction of the image bearing member. 
   
   
     15. The image forming apparatus according to  claim 13 , wherein the adjustment toner image is formed in a position where at least a part of the adjustment toner image is superimposed on an area corresponding to the conveyance area of the recording material having a maximum size, and also a corresponding position outside the conveyance area of the recording material having a predetermined size smaller than the maximum size in a width direction orthogonal to a moving direction of the image bearing member.